This project is designed to complete the evaluation of the relative effectiveness of two cancer-associated biochemical assays for providing decision-making parameters in the clinical management of patients with breast carcinoma. The two cancer-associated biochemical assays are plasma carcinoembryonic antigen (CEA) and serum fast homoarginine sensitive alkaline phosphatase (FHAP). The two assays will be evaluated individually and as a matrix to determine whether or not they provide clinically useful prognostic information postoperatively. The role of postoperatively obtained serial determinations of CEA and FHAP levels, individually and as a matrix, for monitoring disease activity will also be investigated.